Local oscillator (LO) generation for wireless systems can experience signal degradation originating along the LO path and signal interference from remote electrical components. For example, a power amplifier (PA) coupling into a harmonic of an oscillator (OSC) can cause pulling. As a result of the pulling, a voltage-controlled oscillator (VCO) output will not be a single tone anymore and will have unwanted frequency components. For example, the transmitter pulling causes the VCO frequency to spread around its center and will have unwanted sidebands. The unwanted frequency components can degrade the transmitter performance. Traditional fractional divider/multipliers in the LO path can mitigate the PA-to-OSC pulling. However, duty cycle correction in the LO path by the fractional divider/multiplier results in performance degradation of the LO generation. In other instances, I/Q signal generation for baseband processing typically requires a resistor-capacitor-capacitor-resistor (RCCR) circuit implementation. However, the resistor-capacitor (RC) attenuation on the input signal and input impedance observed on the RCCR circuit results in further performance degradation of the LO generation.
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